When J. Baker Hill bought his first global positioning system (GPS) unit in 1998, he went online to find the geographical coordinates for some of the places he had visited around the world. It was then that the 55-year-old Georgian stumbled upon the Degree Confluence Project (DCP), a website that encourages people to visit and document — in words and photos — places on Earth where whole-numbered lines of latitude and longitude intersect. No minutes, no seconds, just integers.

A lifelong geography fan, Hill was instantly hooked on the idea of confluence hunting, which he says tapped into “childhood dreams of intrepid exploration.” Ten years later, Hill is a veteran confluence hunter who can claim 29 confluences in 11 countries.

“When I was a kid,” Hill explained via e-mail, “I was bummed because it seemed all the exploration had already happened, and I loved the stories of the great explorers. It turns out there are many places on the Earth no one has even thought of visiting and documenting.”

Take, for example: 18 degrees north, 16 degrees west, which happens to be a desolate spot on the coast of Mauritania. Or consider the unremarkable cotton field in Togo that straddles 10 degrees north, 1 degree east, or the industrial park outside Calgary, Alberta, which sits atop the invisible crosshairs defined as 51 degrees north, 114 degrees west.

All of these places have been visited and documented by Hill, yet none of them would have beckoned were it not for the DCP. And, given its random nature, that would seem to hold true for all confluences, of which there are 64,442 around the globe (counting each pole as one). Just over 14,000 of those are on land.

Sites in 180 countries

As of this writing, more than 5,400 confluences in 180 countries have been successfully visited. The figure is constantly revised, however, as more visits are indexed.

An all-volunteer project, DCP was launched in 1996 by Alex Jarrett, who kicked things off with a visit to 43 degrees north, 72 degrees west. The precise location is found in a tract of forest about 3 miles, as the crow flies, from the town of Hancock, N.H. It is, as Jarrett duly reported, “a nondescript spot by a swamp.”

In many ways, confluence hunting is similar to geocaching, the global high-tech treasure hunt in which people hide items outdoors — containers filled with trinkets, usually — for others to find, then post the coordinates online. Both pursuits were inspired by the advent of affordable, handheld satellite-based GPS units, and both rely heavily on the Internet.

But where geocaching is more of a lark, confluence hunting feels like real exploration. For one thing, it’s generally more challenging. You may have to climb, trespass or bushwhack your way to the confluence.

Then there is the element of the unknown: Who knows what you’ll find when you get there? And, like the explorers who conquered the poles, confluence hunters — particularly those who are the first to document a confluence — can revel in a sense of discovery.

Perhaps most of all, it has about it an air of inexplicable obsession. Asked why they do it, a confluence hunter might well respond: Because it’s there.

Only it isn’t, really.

For his part, Alex Jarrett has said that he started the project simply because he “liked the idea of visiting a location represented by a round number.”

Also, he “hoped to encourage people to get outside, tromp around in places they normally would never go.”